cis-ocp-v170-5-2-3

name	cis-ocp-v170-5.2.3
description	Minimize admission of containers sharing host IPC namespace (Manual)
category	cis-openshift
version	1.7.0
author	cyberstrike-official
tags	["cis","openshift","kubernetes","redhat","policies","security-context-constraints"]
cis_id	5.2.3
cis_benchmark	CIS Red Hat OpenShift Container Platform Benchmark v1.7.0
tech_stack	["kubernetes","openshift","redhat"]
cwe_ids	[]
chains_with	[]
prerequisites	[]
severity_boost	{}

CIS Red Hat OpenShift Container Platform Benchmark v1.7.0 - Control 5.2.3

Profile Applicability

• Level: 1

Description

Do not generally permit containers to be run with the hostIPC flag set to true.

Rationale

A container running in the host's IPC namespace can use IPC to interact with processes outside the container.

There should be at least one Security Context Constraint (SCC) defined which does not permit containers to share the host IPC namespace.

If you have a requirement to containers which require hostIPC, this should be defined in a separate SCC and you should carefully check RBAC controls to ensure that only limited service accounts and users are given permission to access that SCC.

Impact

Pods defined with Allow Host IPC: true will not be permitted unless they are run under a specific SCC.

Audit Procedure

Use the following command to list all SCCs with allowHostIPC set to false:

oc get scc -o json | jq '.items[] | select(.allowHostIPC==false) |
.metadata.name'

Verify at least one SCC is returned.

Remediation

Create an SCC that sets allowHostIPC to false and take it into use by assigning it to applicable users and groups.

Default Value

By default, the following SCCs do not allow users to run within the host IPC namespace:

"anyuid"
"hostmount-anyuid"
"hostnetwork"
"hostnetwork-v2"
"machine-api-termination-handler"
"node-exporter"
"nonroot"
"nonroot-v2"
"restricted"
"restricted-v2"

References

1. https://docs.openshift.com/container-platform/latest/authentication/managing-security-context-constraints.html
2. https://kubernetes.io/docs/concepts/policy/pod-security-policy/

CIS Controls

Controls Version	Control	IG 1	IG 2	IG 3
v8	13.10 Perform Application Layer Filtering			*
v7	12.9 Deploy Application Layer Filtering Proxy Server